Since you asked, here's my $.02 -
I upgraded to 9.21 (from 9.1), then soon to 9.2.2.
Ran it for several weeks or a month.
I decided that it was somewhat less stable than 9.1 had been, so I went back to 9.1.
Since I had saved a copy of my entire system folder (on my backup volume) before I began the whole upgrade process, it was pretty easy - boot to a system seedie, swap and rename the SFs, copy a few prefs (such as my Stickies file and Pando Calendar stuff), and fix a few aliases.
But YMMV. I have heard from and read about many people who find 9.2.2 to be as stable (or more) than 9.1 and / or 8.6.
- kbeartx
Beige G3 400 MHz ZIF, 768MB RAM, 40GB 5400 RPM IBM, 80GB 7200 RPM WesternDigital, 17" Viewsonic A72f, AV card, SBC Yahoo DSL - shared using a Linksys BEFSR11 and Linksys 5-port hub, 250 MB external SCSI Zip, Yamaha 8424 external SCSI CD burner 'Frankenstein', Kensington TurboMouse5, OS 9.1 and 10.1.5.